Mammoth Mountain

Mammoth Mountain is a lava dome complex in California’s Sierra Nevada at the edge of the Long Valley Caldera, formed by eruptions between about 110,000 and 57,000 years ago and still considered an active volcanic system. Its most notable modern hazard is carbon dioxide released near Horseshoe Lake, where low-oxygen mazuku killed trees across broad areas and has remained under monitoring because of continuing danger. Fatal accidents have also resulted from these gases and from avalanche work on the mountain. At the same time, Mammoth Mountain is one of California’s most important recreation centers, home to the state’s highest ski resort and a major year-round destination.

Mammoth Lakes, California · United States